I seriously dislike it when people suggest that mappers surround their maps with polygons. It increases the filesize, and when done incorrectly, just looks stupid.
Here's a couple of ways to polish your map without having to dump polygons all over it.

Solution one:
Instead of using big ol' polygons, fade the existing surrounding polygons to black. When you've done this, put a large black "blank" sceneries around your map. Good for achieving an underground look, or a slightly enigmatic map.
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Solution two:
Smooth the edges of your map, and then make it look like something. Maybe some kind of field, or wasteland. It's easy to create using a few sceneries, and will often improve the whole look of the map.
[IMAGE]

Hope this helps all you budding mappers.
Thanks to ImageShack for Free Image Hosting

agree. lots of large poly have loads of texture, it's severe for old pc.

true, true i totally agree

i think this should be a sticky because it's a good idea

Can u download new textures?